1. Field of the Invention
The present invention relates to a differential gear lubrication structure. A differential gear case has a pair of boss parts for axial support of a pair of output shafts disposed coaxially with each other. A pair of drive pinions that are combined respectively with output shafts by means of splines and a plurality of differential pinions that engage with the drive pinions are housed in the differential gear case.
The differential pinions are axially supported by pinion shafts which are supported by the differential gear case.
The present application is based on Japanese Patent Application No. Hei. 10-160604, which is incorporated herein by reference.
2. Description of the Related Art
Conventionally known is a gear lubrication structure in Japanese Patent Publication No. Hei. 8-170717, wherein lubricating oil from oil sumps respectively provided at outer ends of the boss parts is supplied to spaces between both the drive pinions via first lubricating oil paths formed between the inner circumferential surfaces of the boss parts and the output shafts and second lubricating oil paths formed between the inner circumferential surfaces of the drive pinions and the output shafts so as to lubricate lubrication points around the pinion shafts, especially the axial supporting parts of the differential pinion shafts.
In the above-described conventional structure, in spite that lubricating oil that is supplied through the second lubricating oil paths is designed so as to flow along the outer circumferential surfaces of the pinion shafts and to the axial supporting parts of the differential pinion shafts, a considerable amount of lubricating oil does not flow along the outer circumferential surface of the pinion shafts but scattered outward and thus further increase in the lubrication efficiency is in demand.